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This module provides support for reading and writing AIFF and AIFF-C files.
AIFF is Audio Interchange File Format, a format for storing digital audio
samples in a file. AIFF-C is a newer version of the format that includes the
ability to compress the audio data.

Note

Some operations may only work under IRIX; these will raise ImportError
when attempting to import the cl module, which is only available on
IRIX.

Audio files have a number of parameters that describe the audio data. The
sampling rate or frame rate is the number of times per second the sound is
sampled. The number of channels indicate if the audio is mono, stereo, or
quadro. Each frame consists of one sample per channel. The sample size is the
size in bytes of each sample. Thus a frame consists of
nchannels*samplesize bytes, and a second’s worth of audio consists of
nchannels*samplesize*framerate bytes.

For example, CD quality audio has a sample size of two bytes (16 bits), uses two
channels (stereo) and has a frame rate of 44,100 frames/second. This gives a
frame size of 4 bytes (2*2), and a second’s worth occupies 2*2*44100 bytes
(176,400 bytes).

Open an AIFF or AIFF-C file and return an object instance with methods that are
described below. The argument file is either a string naming a file or a
file object. mode must be 'r' or 'rb' when the file must be
opened for reading, or 'w' or 'wb' when the file must be opened for writing.
If omitted, file.mode is used if it exists, otherwise 'rb' is used. When
used for writing, the file object should be seekable, unless you know ahead of
time how many samples you are going to write in total and use
writeframesraw() and setnframes().
The open() function may be used in a with statement. When
the with block completes, the close() method is called.

Return a list of markers in the audio file. A marker consists of a tuple of
three elements. The first is the mark ID (an integer), the second is the mark
position in frames from the beginning of the data (an integer), the third is the
name of the mark (a string).

Close the AIFF file. After calling this method, the object can no longer be
used.

Objects returned by open() when a file is opened for writing have all the
above methods, except for readframes() and setpos(). In addition
the following methods exist. The get*() methods can only be called after
the corresponding set*() methods have been called. Before the first
writeframes() or writeframesraw(), all parameters except for the
number of frames must be filled in.

Specify the compression type. If not specified, the audio data will
not be compressed. In AIFF files, compression is not possible.
The name parameter should be a human-readable description of the
compression type as a bytes array, the type parameter should be a
bytes array of length 4. Currently the following compression types
are supported: b'NONE', b'ULAW', b'ALAW', b'G722'.